Golf balls with cores or intermediate layers prepared from highly-neutralized ethylene terpolymers and organic acids

ABSTRACT

Described are golf balls comprising cores or intermediate layers prepared from thermoplastic compositions having coefficients of restitution equal to or greater than 0.83 and PGA compression greater than 100. Also described is a composition comprising or prepared from (a) at least one aliphatic, mono-functional organic acid having from 16 to 20 carbon atoms, wherein the organic acid is unsaturated and linear; (b) an ethylene acid copolymer consisting essentially of copolymerized comonomers of ethylene and from 18 to 24 weight % of copolymerized comonomers of at least one C 3  to C 8  α,β ethylenically unsaturated carboxylic acid, based on the total weight of the ethylene acid copolymer, having a melt index from about 200 to about 600 g/10 minutes; wherein the combined acid moieties of (a) and (b) are nominally neutralized to a level from about 120% to about 200%; and optionally (c) filler.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to golf balls with cores or intermediate layersprepared from melt-processible thermoplastic compositions comprisingneutralized ethylene, C₃ to C₈ α,β ethylenically unsaturated carboxylicacid copolymers and organic acids.

2. Description of Related Art

Several patents and publications are cited in this description in orderto more fully describe the state of the art to which this inventionpertains. The entire disclosure of each of these patents andpublications is incorporated by reference herein.

Premium golf balls include wound balls, two-piece balls and multilayeredballs. Wound balls may have a spherical molded center, elastomericthread-like material wound around the center, and either a thermoplasticor thermoset cover. Two-piece balls have a spherical molded core coveredwith a thin layer of thermoplastic or thermoset material. Multilayeredballs have a spherical molded core, a cover, and one or moreintermediate layers between the core and the cover.

Centers for wound balls and cores for two-piece and multi-layer ballshave been made using a thermoset rubber such as polybutadiene rubber.With thermoset rubber, complex multi-step processes are needed to makecores and centers. These processes result in scrap that is difficult torecycle. Attempts to solve these difficulties by substituting athermoplastic for the thermoset rubber have had limited success.

Thermoplastic ionomers of copolymers of alpha olefins, particularlyethylene, and C₃₋₈ α,β ethylenically unsaturated carboxylic acids havefound utility in golf ball components such as covers, and otherapplications. U.S. Pat. No. 3,264,272 teaches methods for making suchionomers. The acid copolymers on which the ionomers are based may beprepared as described in U.S. Pat. No. 4,351,931.

A wide range of cations is known for neutralizing acid moieties in theacid copolymer, including lithium, sodium, potassium, magnesium,calcium, barium, lead, tin, zinc, aluminum, and combinations of suchcations and the degree of neutralization is known to vary over a widerange. Neutralization to 90% and higher, including up to 100%, is known,but such a high degree of neutralization can result in a loss ofmelt-processibility or properties such as elongation and toughness. Thisis particularly so for copolymers with high acid levels.

U.S. Pat. Nos. 5,688,869; 6,150,470; 6,277,921; 6,433,094; 6,451,923;6,573,335 and 6,800,695 disclose compositions, and golf ball coverscomprising the compositions, comprising metal cation neutralized highacid ionomer resins comprising copolymers of greater than 16% by weightof an alpha, beta-unsaturated carboxylic acid and the balance analpha-olefin, of which about 10 to about 90% of the carboxyl groups ofthe copolymer are neutralized with metal cations.

Ionomers have also been modified with fatty acids. For example, U.S.Pat. No. 6,777,472 discloses a thermoplastic composition that ismelt-processable consisting essentially of (a) from 20 to 45 weightpercent aliphatic, mono-functional organic acid(s) having fewer than 36carbon atoms or salt(s) thereof; and (b) ethylene, C₃ to C₈ alpha,betaethylenically unsaturated carboxylic acid copolymer(s) ormelt-processible ionomer(s) thereof, wherein greater than 90% of all theacid of (a) and (b) is neutralized by concurrently or subsequentlyadding to the melt blend of (a) and (b) an amount of a cation sourcenecessary to obtain greater than 90% neutralization.

Modified ionomers have been used as golf ball components. For example,U.S. Pat. No. 6,565,456 discloses multilayer golf balls comprising asolid core, a surrounding layer, an intermediate layer and a cover,wherein at least one of the surrounding layer, the intermediate layer orthe cover is formed of a heated mixture comprising (a) anolefin-carboxylic acid-optional carboxylate random copolymer and/or (d)a metal ion-neutralized olefin-carboxylic acid-optional carboxylaterandom copolymer; (b) a fatty acid or derivative; and (c) a neutralizingbasic inorganic metal compound.

U.S. Pat. No. 6,653,382 discloses golf balls comprising a thermoplasticpolymer consisting essentially of at least one of (a) E/X/Y copolymerswhere E is ethylene, X is a C₃ to C₈ alpha,beta ethylenicallyunsaturated carboxylic acid, and Y is a softening co-monomer of theE/X/Y copolymers, wherein X is about 3-30 weight % of the E/X/Ycopolymer, or partially neutralized ionomers thereof, and Y is about0-30 weight % of the E/X/Y copolymer; and (b) one or more aliphatic,mono-functional organic acids having fewer than 36 carbon atoms or saltsthereof being present in the range of about 25 to about 150 parts perhundred parts by weight of the E/X/Y copolymer, wherein greater than 90%of all the acid of (a) and of (b) is neutralized with a cation source.

US Patent Application Publication 2002/0111407 discloses golf ballscomprising a base resin comprising a (metal ion-neutralized)olefin-unsaturated carboxylic acid-unsaturated carboxylate ternaryrandom copolymer and optionally a (metal ion-neutralized)olefin-unsaturated carboxylic acid binary random copolymer blended withspecific proportions of a fatty acid and/or fatty acid derivative and abasic inorganic metal compound capable of neutralizing acidic groupsleft unneutralized in the base resin and fatty acid.

U.S. Pat. No. 6,953,820 discloses a composition, and golf ballscomprising the composition, comprising a thermoplastic polymer blendwhich has a coefficient of restitution of at least 0.785 and an Atticompression of no more than 100, wherein the blend consists essentiallyof at least one (a) E/X/Y copolymers where E is ethylene, X is a mixtureof at least two C₃ to C₈ alpha,beta ethylenically unsaturated carboxylicacids, and Y is a softening comonomer or ionomers of the E/X/Ycopolymers wherein X is about 3-30 weight % of the E/X/Y copolymer, andY is 0 to about 30 weight % of the E/X/Y copolymer; and (b) one or morealiphatic, mono-functional organic acids having fewer than 36 carbonatoms or salts thereof, wherein greater than 90% of all the acid of (a)and of (b) is neutralized.

It is desirable to provide a high performance material to be used in thecores, centers or intermediate layers of golf balls.

SUMMARY OF THE INVENTION

The invention provides a thermoplastic composition comprising orprepared from:

(a) at least one aliphatic, monofunctional organic acid having 4 to 36carbon atoms, wherein the longest carbon chain of the acid is optionallysubstituted with from one to three substituents independently selectedfrom C₁ to C₈ alkyl groups;

(b) at least one ethylene acid copolymer consisting essentially ofcopolymerized comonomers of ethylene, from about 12 to about 25 weight %of copolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid, and from about 0.5 to about 10 weight % ofcopolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid ester, based on the total weight of theethylene acid copolymer, having a melt index from about 200 to about 600g/10 minutes measured according to ASTM D1238 at 190° C. using a 2160 gweight;

wherein the combined acid moieties of (a) and (b) are nominallyneutralized to a level from about 90% to about 220%; and

wherein the thermoplastic composition when formed into a sphere of 1.50to 1.68 inches in diameter has a coefficient of restitution equal to orgreater than 0.86, measured by firing the sphere at an initial velocityof 125 feet/second against a steel plate positioned 3 feet from thepoint where initial velocity is determined and dividing the velocity ofrebound from the plate by the initial velocity and has a PGA compressiongreater than 110.

Also provided is a golf ball comprising a core and a cover andoptionally at least one intermediate layer positioned between the coreand the cover, wherein the core or an intermediate layer when presentcomprises or is prepared from the thermoplastic composition describedabove.

DETAILED DESCRIPTION OF THE INVENTION

The following definitions apply to the terms as used throughout thisspecification, unless otherwise limited in specific instances.

The technical and scientific terms used herein have the meanings thatare commonly understood by one of ordinary skill in the art to whichthis invention belongs. In case of conflict, the present specification,including the definitions herein, will control. Tradenames are inuppercase.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “containing,” “characterized by,” “has,” “having” or anyother variation thereof, are intended to cover a non-exclusiveinclusion. For example, a process, method, article, or apparatus thatcomprises a list of elements is not necessarily limited to only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus.

The transitional phrase “consisting of” excludes any element, step, oringredient not specified in the claim, closing the claim to theinclusion of materials other than those recited except for impuritiesordinarily associated therewith. When the phrase “consists of” appearsin a clause of the body of a claim, rather than immediately followingthe preamble, it limits only the element set forth in that clause; otherelements are not excluded from the claim as a whole.

The transitional phrase “consisting essentially of” limits the scope ofa claim to the specified materials or steps and those that do notmaterially affect the basic and novel characteristic(s) of the claimedinvention. A ‘consisting essentially of’ claim occupies a middle groundbetween closed claims that are written in a ‘consisting of’ format andfully open claims that are drafted in a ‘comprising’ format. Optionaladditives as defined herein, at levels that are appropriate for suchadditives, and minor impurities are not excluded from a composition bythe term “consisting essentially of”.

When a composition, a process, a structure, or a portion of acomposition, a process, or a structure, is described herein using anopen-ended term such as “comprising,” unless otherwise stated thedescription also includes an embodiment that “consists essentially of”or “consists of” the elements of the composition, the process, thestructure, or the portion of the composition, the process, or thestructure.

The articles “a” and “an” may be employed in connection with variouselements and components of compositions, processes or structuresdescribed herein. This is merely for convenience and to give a generalsense of the compositions, processes or structures. Such a descriptionincludes “one or at least one” of the elements or components. Moreover,as used herein, the singular articles also include a description of aplurality of elements or components, unless it is apparent from aspecific context that the plural is excluded.

The term “or”, as used herein, is inclusive; that is, the phrase “A orB” means “A, B, or both A and B”. More specifically, a condition “A orB” is satisfied by any one of the following: A is true (or present) andB is false (or not present); A is false (or not present) and B is true(or present); or both A and B are true (or present). Exclusive “or” isdesignated herein by terms such as “either A or B” and “one of A or B”,for example.

The term “about” means that amounts, sizes, formulations, parameters,and other quantities and characteristics are not and need not be exact,but may be approximate and/or larger or smaller, as desired, reflectingtolerances, conversion factors, rounding off, measurement error and thelike, and other factors known to those of skill in the art. In general,an amount, size, formulation, parameter or other quantity orcharacteristic is “about” or “approximate” whether or not expresslystated to be such.

In addition, the ranges set forth herein include their endpoints unlessexpressly stated otherwise. Further, when an amount, concentration, orother value or parameter is given as a range, one or more preferredranges or a list of upper preferable values and lower preferable values,this is to be understood as specifically disclosing all ranges formedfrom any pair of any upper range limit or preferred value and any lowerrange limit or preferred value, regardless of whether such pairs areseparately disclosed. The scope of the invention is not limited to thespecific values recited when defining a range.

When materials, methods, or machinery are described herein with the term“known to those of skill in the art”, “conventional” or a synonymousword or phrase, the term signifies that materials, methods, andmachinery that are conventional at the time of filing the presentapplication are encompassed by this description. Also encompassed arematerials, methods, and machinery that are not presently conventional,but that will have become recognized in the art as suitable for asimilar purpose.

Unless stated otherwise, all percentages, parts, ratios, and likeamounts, are defined by weight.

As used herein, the term “copolymer” refers to polymers comprisingcopolymerized units resulting from copolymerization of two or morecomonomers. In this connection, a copolymer may be described herein withreference to its constituent comonomers or to the amounts of itsconstituent comonomers, for example “a copolymer comprising ethylene and18 weight % of acrylic acid”, or a similar description. Such adescription may be considered informal in that it does not refer to thecomonomers as copolymerized units; in that it does not include aconventional nomenclature for the copolymer, for example InternationalUnion of Pure and Applied Chemistry (IUPAC) nomenclature; in that itdoes not use product-by-process terminology; or for another reason. Asused herein, however, a description of a copolymer with reference to itsconstituent comonomers or to the amounts of its constituent comonomersmeans that the copolymer contains copolymerized units (in the specifiedamounts when specified) of the specified comonomers. It follows as acorollary that a copolymer is not the product of a reaction mixturecontaining given comonomers in given amounts, unless expressly stated inlimited circumstances to be such. The term “terpolymer” refers topolymers consisting essentially of three monomers.

Previously known organic acid-modified ethylene acid terpolymers mayhave coefficients of restitution less than 0.86 and PGA compression lessthan 100. It is desirable, however, to provide a composition having ahigher coefficient of restitution. Accordingly, provided herein is athermoplastic composition comprising or prepared from:

(a) at least one aliphatic, monofunctional organic acid having 4 to 36carbon atoms;

(b) at least one ethylene acid copolymer consisting essentially ofcopolymerized comonomers of ethylene, from about 5 to about 18 weight %of copolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid, and from about 15 to about 30 weight % ofcopolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid ester, based on the total weight of theethylene acid copolymer, having a melt index from about 30 to about 120g/10 minutes measured according to ASTM D1238 at 190° C. using a 2160 gweight;

wherein the combined acid moieties of (a) and (b) are nominallyneutralized to a level from about 80% to about 100% or to about 150%.

Acid Copolvmers

The acid copolymers used to make the compositions described herein arepreferably “direct” acid copolymers. In “direct” copolymers, thecopolymerized monomers are part of the polymer backbone or chain. Incontrast, in graft copolymers, another comonomer is attached tonon-terminal repeat units in an existing polymer chain, often by asubsequent free radical reaction.

When combined with other components as described herein, an ethyleneterpolymer consisting essentially of copolymerized comonomers ofethylene, about 12 to about 25 weight % of copolymerized comonomers of aC₃ to C₈ α,β ethylenically unsaturated carboxylic acid, and about 0.5 toabout 10 weight % of copolymerized comonomers of a C₃ to C₈ α,βethylenically unsaturated carboxylic acid ester having melt index flowrate of about 200 g/10 min to about 600 g/10 min or greater at 190° C.using a 2160 g weight is useful for preparing compositions withcoefficients of restitution greater than 0.86, preferably greater than0.87 or 0.88.

The terpolymer resins have melt index flow rates of about 200 g/10 minto about 600 g/10 min, or greater, at 190° C. using a 2160 g weight. Ofnote are terpolymer resins having melt index flow rates from about 250g/10 min to about 400 g/10 min. Also of note are terpolymer resinshaving melt index flow rates from about 400 g/10 min to about 600 g/10min.

Preferred are terpolymers and compositions comprising the terpolymerswherein the copolymerized comonomers of C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid are acrylic acid or methacrylic acid and thecopolymerized comonomers of C₃ to C₈ α,β ethylenically unsaturatedcarboxylic acid esters are C₁-C₄ alkyl esters of acrylic acid ormethacrylic acid. More preferred are ethylene/acrylic acid/alkylacrylate terpolymers and ethylene/methacrylic acid/alkyl acrylateterpolymers.

Ethylene acid terpolymers with high levels of acid may be prepared byuse of “co-solvent technology” as described in U.S. Pat. No. 5,028,674or by employing somewhat higher pressures than those at which copolymerswith lower acid can be prepared.

Ethylene/acrylic acid/alkyl acrylate terpolymers are of note becauseacrylic acid provides more acid moieties than an equal weight ofmethacrylic acid. Preferred are ethylene/acrylic acid/n-butyl acrylateterpolymers, including those wherein copolymerized acrylic acidcomprises from 15 to 25 weight % of the terpolymer and copolymerizedn-butyl acrylate comprises from 1 to 10 weight % of the terpolymer. Morepreferred are those wherein copolymerized acrylic acid comprises from 20to 25 weight % and copolymerized n-butyl acrylate comprises from 1 to 5weight %. A specific terpolymer comprises 20.8 weight % of copolymerizedacrylic acid and 2.0 weight % of copolymerized n-butyl acrylate.

Of note are ethylene/methacrylic acid/n-butyl acrylate terpolymers,including those wherein copolymerized methacrylic acid comprises from 15to 25 weight % of the terpolymer and copolymerized n-butyl acrylatecomprises from 3 weight % to 10 weight % of the terpolymer.

Mixtures of terpolymers may be used, provided that the combined amountsof the comonomers of the blended terpolymers and the properties of themixture (for example, melt index) fall within the ranges describedabove, such as a composition comprising a mixture of about 4 parts of aterpolymer with 20.8 weight % of copolymerized acrylic acid and 2.0weight % of copolymerized n-butyl acrylate with MI of 474 and about 1part of a terpolymer with 6.2 weight % of copolymerized acrylic acid and28.0 weight % nBA with MI of 300.

Ionomers

Unmodified, melt processible ionomers may be prepared from acidcopolymers described above by methods known in the art. By “unmodified”,it is meant that the ionomers are not blended with any material that hasbeen added for the purpose of modifying the properties of the unblendedionomer. Ionomers include partially neutralized acid copolymers,particularly copolymers prepared from copolymerization of ethylene andacrylic acid or methacrylic acid. The unmodified ionomers may beneutralized to any level that does not result in an intractable (notmelt processible) polymer that does not have useful physical properties.Preferably, about 15 to about 90%, more preferably about 50 to about 75%of the acid moieties of the acid copolymer are neutralized to formcarboxylate groups. Preferred counterions for the carboxylate groupsinclude alkali metal cations, alkaline earth metal cations, transitionmetal cations, and combinations of two or more of these metal cations.

Cations useful in making the unmodified ionomers include lithium,sodium, potassium, magnesium, aluminum, calcium, barium, or zinc, orcombinations of such cations. Magnesium cations or calcium cations arepreferred.

Organic acids and Salts

Suitable organic acids include, without limitation, aliphatic,monofunctional organic acids having 4 to 36 carbon atoms, optionallysubstituted with from one to three substituents independently selectedfrom C₁ to C₈ alkyl groups. The organic acids may be saturated orunsaturated, and, if unsaturated, may include more than onecarbon-carbon double bond. The term “monofunctional” refers to acidswith one carboxylic acid moiety. The suitable organic acids include C₄to C₃₆ (for example C₁₈), or C₆ to C₂₆, or C₆ or C₁₂, or C₁₆ to C₂₄acids.

Examples of suitable organic acids include, but are not limited to,caproic acid, caprylic acid, capric acid, lauric acid, stearic acid,isostearic acid, behenic acid, erucic acid, oleic acid, iso-oleic acid,and linoleic acid. Naturally derived organic fatty acids such aspalmitic, stearic, oleic, erucic, behenic acids, and mixtures thereofmay also be employed.

As known in the art, commercial grades of organic acids may include anumber of structurally different organic acids of varying lesseramounts. As used herein, unless otherwise specified in limitedcircumstances, a composition that comprises a named acid may alsoinclude other acids that are present in commercial grades of the namedacid, at levels that are proportional to their levels in the commercialgrade. Furthermore, when the transitional term “consisting essentiallyof” is applied to compositions that comprise a named acid, other acidsthat are present in commercial grades of the named acid, at levels thatare proportional to their levels in the commercial grade, are notexcluded from the composition.

Saturated acids of particular note include stearic acid and behenicacid. Saturated linear organic acids (for example stearic acid andbehenic acid) are acids comprising only one CH₃ (methyl) and no CH(methenyl) moieties.

Unsaturated linear organic acids (for example oleic acid and erucicacid) are acids that have only one CH₃ moiety and at least onecarbon-carbon double bond. They include any number of CH₂ (methylene)groups, within the carbon count limits set forth above. Monounsaturatedacids contain one carbon-carbon double bond. Of note are linear,unsaturated (including multi-unsaturated) organic acids having from 16to 24 carbon atoms, including but not limited to oleic acid, erucic acidand linoleic acid. Naturally derived organic fatty acids such as(notably) oleic acid, and mixtures thereof, may be used. Oleic acid iscommercially available under tradenames INDUSTRENE 106 or INDUSTRENE 206(PMC Biogenix of Middlebury, Conn.) or PRIOLENE 6900 or PRIOLENE 6910(Croda Uniqema of New Castle, Del.). Erucic acid is availablecommercially under the trade name JARIC 22:1 from Jarchem IndustriesInc. of Newark, N.J.) or as Prifrac 2990 from Uniqema of Wilton,England.

Acids wherein the longest carbon chain of the acid is substituted withfrom one to three C₁ to C₈ alkyl substituents, preferably methyl groups,are referred to herein as branched acids. Saturated, branched organicacids are acids comprising at least one CH (methenyl) moiety and atleast two CH₃ (methyl) moieties. Of note are saturated, branched organicacids wherein the longest carbon chain of the acid is substituted withone C₁ to C₈ alkyl group. Also of note is a saturated, branched organicacid, preferably having from 6 to 24 carbon atoms, such as the C₁₈saturated branched organic acid, “iso-stearic acid,” also known asisooctadecanoic acid or 16-methyl-heptadecanoic acid.

Unsaturated branched acids are acids comprising at least onecarbon-carbon double bond, at least two CH₃ (methyl) moieties and atleast one CH (methenyl) moiety. They may include any number of CH₂(methylene) groups, within the molecular weight limits set forth above.Of note are unsaturated, branched organic acids wherein the longestcarbon chain of the acid is substituted with one C₁ to C₈ alkyl group.Also of note is an unsaturated, branched organic acid, preferably havingfrom 6 to 24 carbon atoms, such as the C₁₈ monounsaturatedmethyl-branched organic acid known as “iso-oleic acid.”

While it may be useful for the organic acids (and salts) to have a lowvolatility when being melt-blended with the acid copolymer or ionomer,volatility has been found to not be limiting when preparing blends withhigh nominal neutralization levels, particularly above 100%. At 100%nominal neutralization (i.e., sufficient basic compound is added suchthat all acid moieties in the copolymer and organic acid are nominallyneutralized), or when the use of an excess of neutralizing agent resultsin a nominal neutralization level that is even greater than 100%, thevolatility of these components is not significant. Accordingly, organicacids with lower molecular weights, such as C₄ and C₆ acids, may beused. It is preferred, however, that the organic acid (or salt) benon-volatile and non-migratory. By non-volatile, it is meant that theydo not evaporate or sublimate significantly at temperatures of meltblending of the acid with the acid copolymer. By non-migratory, it ismeant that the acid does not bloom to the surface of the polymericarticle under normal storage conditions at ambient temperatures.

Preferably the organic acids are present in about 5 weight % to about 60weight %, and more preferably, from about 30 to about 50 weight % orfrom about 35 to about 46 weight % of the total weight of ionomer andorganic acid salt, based on the amount of organic acid added to thecomposition in its non-neutralized or free-acid form.

The cations of the organic acid salts may be any of a wide variety,including the lithium, sodium, zinc, potassium, barium, bismuth,strontium, magnesium, aluminum or calcium salts of the organic acids.Magnesium salts or calcium salts are preferred.

Process for making the Ionomer Composition

The melt-processible, modified ionomer blends may be produced by heatinga mixture of the carboxylic acid copolymer(s) or ionomer(s), the organicacid(s) or salt(s) thereof, and at least one basic compound capable ofneutralizing the combined acid moieties of the acid copolymer and theorganic acid. For example, the components of the composition may bemixed by

-   -   (a) Melt-blending ethylene α,β-ethylenically unsaturated C₃₋₈        carboxylic acid copolymer(s) or ionomer(s) thereof as described        above that are not neutralized to a level that renders them        intractable (not melt-processible) with one or more organic        acids as described above or salts thereof, and concurrently or        subsequently    -   (b) Adding an amount of a basic compound capable of        neutralization of the acid moieties in the acid copolymer and in        the organic acid that is sufficient to achieve nominal        neutralization levels of about 120% to about 200% or above.

This procedure need not employ an inert diluent such as a solvent.Treatment of acid copolymers and organic acids with basic compounds inthis way enables the compositions described herein to be neutralized toa level higher than that which would result in loss of meltprocessibility and properties for the ionomer alone. For example, anacid copolymer blended with organic acid(s) may be nominally neutralizedto a level of over 120% without losing melt processibility. Also,nominal neutralization over 120% reduces the volatility of the organicacids.

The acid copolymer(s) or unmodified, melt-processible ionomer(s) may bemelt-blended with the organic acid(s) or salt(s) and other polymers inany manner known in the art. For example, a salt and pepper blend of thecomponents may be made and then melt-blended in an extruder. Themelt-processible, acid copolymer/organic-acid-or-salt blend may betreated with the basic compound by methods known in the art, such asmelt-mixing. For example, a Werner & Pfleiderer twin-screw extruder maybe used to mix the acid copolymer and the organic acid and treat withthe basic compound at the same time. It is desirable that the mixing beconducted so that the components are intimately mixed, allowing thebasic compound to neutralize the acidic moieties.

The amount of basic metal compound capable of neutralizing acidic groupsin the acid copolymer and the organic acid(s) may be determined byadding the stoichiometric amount of the basic compound calculated toneutralize a target amount of acid moieties in the acid copolymer andorganic acid(s) in the blend (herein referred to as “% nominalneutralization” or “nominally neutralized”). Thus, sufficient basiccompound is made available in the blend so that, in aggregate, theindicated level of nominal neutralization could be achieved. Of note arenominal neutralization levels of about 120% to about 150%, about 150% toabout 180%, or about 150% to about 200%.

Suitable basic compounds include compounds of alkali metals, such aslithium, sodium or potassium, transition metal ions and/or alkalineearth metal and mixtures or combinations of such cations. They includeformates, acetates, nitrates, hydrogen carbonates, carbonates, oxides,hydroxides or alkoxides of the ions of alkali metals, and formates,acetates, nitrates, oxides, hydroxides or alkoxides of the ions ofalkaline earth metals and transition metals. Basic compounds withmagnesium or calcium ions, such as the corresponding formate, acetate,hydroxide, oxide, alkoxide, etc.; including magnesium hydroxide, are ofnote.

It is desirable to run the blending/neutralization process with anextruder equipped with a vacuum port to remove any excess volatilesincluding moisture. Moisture may have a negative impact on subsequentmolding operations in that excess moisture and volatiles may createunwanted foaming and voids in the molded article.

Of note is the composition wherein the overall salt of the composition(“overall salt” is a number of moles that is equal to the total numberof moles of carboxylate anions) comprises at least about 75 equivalent %magnesium counterions or calcium counterions. While other cations may bepresent, the equivalent percentage of magnesium salts or calcium saltsin the final blended ionomeric composition is preferably at least about75 equivalent %, more preferably at least about 80 equivalent %, andmost preferably at least about 90 equivalent % based on the total saltpresent in the blended composition.

The basic compound(s) may be added neat to the acid copolymer or ionomerthereof and the organic acid or salt thereof. The basic compound(s) mayalso be premixed with a polymeric material such as an acid copolymer, toform a “masterbatch” that may be added to the acid copolymer or ionomerthereof and the organic acid or salt thereof. A notable masterbatchcomprising about 40 to 60 weight % of a copolymer of ethylene, acrylicacid or methacrylic acid, and optionally an alkyl acrylate wherein thealkyl group has from 1 to 4 carbon atoms; and about 40 to 60 weight % ofa basic compound as described above (e.g., Mg(OH)₂). Of note arecompositions comprising or prepared from

(1) about 30 to about 50 weight % of at least one aliphatic, unsaturatedorganic acid having from 16 to 22 carbon atoms;

(2) about 30 to about 60 weight % of an ethylene acid terpolymerconsisting essentially of ethylene and from 15 to 25 weight % ofcopolymerized comonomers of acrylic acid or methacrylic acid based onthe total weight of the ethylene acid copolymer and from 1 to 10 weight% of an alkyl acrylate wherein the alkyl group has from 1 to 4 carbonatoms (such as butyl acrylate) based on the total weight of the ethyleneacid copolymer, having a melt index from about 200 to about 600 g/10minutes;

(3) about 5 to about 15 weight % of a copolymer of ethylene, 5 to 10weight % of acrylic acid or methacrylic acid based on the total weightof the copolymer, and 15 to 30 weight % of an alkyl acrylate wherein thealkyl group has from 1 to 4 carbon atoms (such as butyl acrylate) basedon the total weight of the copolymer having a melt index from about 200to about 600 g/10 minutes; wherein the amounts of (1) and (2) and (3)based on the total weight of the composition;

wherein the combined acid moieties of (1) and (2) and (3) are nominallyneutralized to a level from about 90% to about 220%.

Other Components

The compositions may additionally comprise small amounts of optionalmaterials including additives for use in polymeric materials. Examplesof suitable additives include, without limitation, plasticizers,stabilizers including viscosity stabilizers and hydrolytic stabilizers,primary and secondary antioxidants such as for example IRGANOX 1010,ultraviolet ray absorbers and stabilizers, anti-static agents, dyes,pigments or other coloring agents, fire-retardants, lubricants,processing aids, slip additives, antiblock agents such as silica ortalc, release agents, and/or mixtures thereof. Additional optionaladditives may include inorganic fillers as described below; acidcopolymer waxes, such as for example Honeywell wax AC540; TiO₂, which isused as a whitening agent; optical brighteners; surfactants; and othercomponents known in the art of golf ball manufacture to be useful butnot critical to golf ball performance and/or acceptance. Many suchadditives are described in the Kirk Othmer Encyclopedia of ChemicalTechnology, 5^(th) edition, John Wiley & Sons (Hoboken, 2005).

These additives may be present in the compositions in quantities thatmay be from 0.01 to 15 weight %, preferably from 0.01 to 10 weight %, orfrom 0.01 to 5 weight % of the total composition, so long as they do notdetract from the basic and novel characteristics of the composition anddo not significantly adversely affect the performance of the compositionor golf ball prepared from the composition.

The optional incorporation of such conventional ingredients into thecompositions may be carried out by any known process, for example, bydry blending, by extruding a mixture of the various constituents, by theconventional masterbatch technique, or the like.

Filler

Various optional fillers may be added to compositions to reduce cost, toaffect rheological, mixing and physical properties such as density, flexmodulus, hardness (e.g. Shore D), mold release, and/or melt flow indexand the like, to increase or decrease weight, and/or to reinforce thematerial. The amount of filler employed is primarily a function ofweight requirements and weight distribution of the golf ball. Thefillers may be used to adjust the properties of a golf ball layer,reinforce the layer, or for any other purpose. For example, thecompositions may be reinforced by blending with a wide range ofdensity-adjusting fillers, e.g., ceramics, glass spheres (solid orhollow, and filled or unfilled), and fibers, inorganic particles, andmetal particles, such as metal flakes, metallic powders, oxides, andderivatives thereof, as is known in the art.

Fillers may be used to modify the weight of the golf ball to meetrequired limits, by imparting additional density to compositions of thepreviously described components. Filler may be included in one or morelayers of the golf ball, such as the core or intermediate layer(s), theselection being dependent upon the type of golf ball desired (i.e.,two-piece, wound or multilayer), as more fully detailed below.

The filler may be inorganic, having a density from about 4 grams/cubiccentimeter (g/cc), or from about 5 g/cc, to about 10 g/cc or higher andmay be present in amounts between 0 and about 60 weight % based on thetotal weight of the composition. Preferably, enough filler is used sothat the ball has an overall density of 1.14 gm/cc.

Examples of useful fillers include metals such as titanium, tungsten,aluminum, bismuth, nickel, molybdenum, iron, steel, lead, copper, brass,boron, boron carbide whiskers, bronze, cobalt, beryllium, zinc, tin,metal oxides including zinc oxide, iron oxide, aluminum oxide, tinoxide, titanium oxide, magnesium oxide, zinc oxide and zirconium oxide,as well as other well known corresponding salts and oxides thereof.Other preferred fillers include barium sulfate, lead silicate, tungstencarbide, limestone (ground calcium/magnesium carbonate), zinc sulfate,calcium carbonate, zinc carbonate, barium carbonate, clay, tungsten,silicas, and mixtures of any of these. Preferably the filler material isnon-reactive or almost non-reactive. Of note are barium sulfate andtungsten powder fillers. Crystalline tungsten powder having a specificgravity of about 19.3 g/cc is available from Alldyne PowderTechnologies, Kulite Tungsten Corporation or Buffalo TungstenIncorporated.

Fillers may be employed in a finely divided form, for example, in a sizeless than about 20 mesh U.S. standard size, preferably from about 100mesh to about 1000 mesh, except for fibers and flock, which may beelongated. Flock and fiber sizes are desirably small enough tofacilitate processing. Filler particle size may depend upon desiredeffect, cost, ease of addition, and dusting considerations.

When filler is used in a particular composition, the coefficient ofrestitution (COR), as described below, will decrease roughlyproportionally to the volumetric displacement of the polymer by thefiller. For example, if 5 volume % of filler is used to provide adesired specific gravity, then the COR of a sphere made from the filledcomposition may be about 95% of the COR of a comparable sphere made fromthe unfilled composition. When tungsten is used as a filler with thecompositions described herein, the COR of a sphere of about 1.53 inchesin diameter may decrease about 0.015 to 0.020 compared to a sphere ofthe same size prepared from the corresponding unfilled composition,depending on the amount of tungsten that is present in the filledcomposition.

Of note is a thermoplastic composition comprising or prepared from: 90to 99.9 volume %, 95 to 99.9 volume %, or 97 to 99.9 volume % of a blendcomprising

(a) at least one aliphatic, monofunctional organic acid having 4 to 36carbon atoms, wherein the longest carbon chain of the acid is optionallysubstituted with from one to three substituents independently selectedfrom C₁ to C₈ alkyl groups;

(b) at least one ethylene acid copolymer consisting essentially ofcopolymerized comonomers of ethylene, from about 12 to about 25 weight %of copolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid, and from about 0.5 to about 10 weight % ofcopolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid ester, based on the total weight of theethylene acid copolymer, having a melt index from about 200 to about 600g/10 minutes measured according to ASTM D1238 at 190° C. using a 2160 gweight;

wherein the combined acid moieties of (a) and (b) are nominallyneutralized to a level from about 90% to about 200;

and further comprising 0.1 to 10, 0.1 to 3, or 0.1 to 5 volume % offiller, based on the total volume of the thermoplastic composition.

Blowing or Foaming Agents

The compositions may be foamed by the addition of at least one physicalor chemical blowing or foaming agent or by blending with polymeric,ceramic, metal, and glass microspheres. The use of a foamed polymerallows the golf ball designer to adjust the density or mass distributionof the ball to adjust the angular moment of inertia, and thus, the spinrate and performance of the ball. Foamed materials also offer apotential cost savings due to the reduced use of polymeric material.

Useful blowing or foaming agents include but are not limited to organicblowing agents, such as azobisformamide; azobisisobutyronitrile;diazoaminobenzene; N,N-dimethyl-N,N-dinitroso terephthalamide;N,N-dinitrosopentamethylene-tetramine; benzenesulfonyl-hydrazide;benzene-1,3-disulfonyl hydrazide; diphenylsulfon-3-3, disulfonylhydrazide; 4,4′-oxybis benzene sulfonyl hydrazide; p-toluene sulfonylsemicarbizide; barium azodicarboxylate; butylamine nitrile; nitroureas;trihydrazino triazine; phenyl-methyl-uranthan; p-sulfonhydrazide;peroxides; and inorganic blowing agents such as ammonium bicarbonate andsodium bicarbonate. A gas, such as air, nitrogen, carbon dioxide, etc.,may also be injected into the composition during the injection moldingprocess.

A foamed composition may be formed by blending microspheres with thecomposition either during or before the molding process. Polymeric,ceramic, metal, and glass microspheres up to about 1000 micrometers indiameter are useful, and may be solid or hollow and filled or unfilled.

Of note is an article comprising a foamed composition, such as a ballcomprising a core or center prepared from the foamed composition. Inaddition to golf balls, such balls include baseballs and softballs.Either injection molding or compression molding may be used to form alayer or a core including a foamed polymeric material.

The compositions described herein may be injection molded or compressionmolded into various shaped articles, including cores or intermediatelayers for golf balls as described below. For example but notlimitation, injection molding conditions may include temperatures,pressures and cycle times as indicated in Table A.

TABLE A Temperature Injection Cycle Times (° C.) Pressure (mPa) (sec)Melt 160-260 Packing 25-180 Filling and Mold Front/Back 10-30 Hold 5-15Packing 40-90 Hold 15-30 Cooling Time 50-100 Screw Retraction 5-50

Golf Ball Construction

The compositions described herein may be used with any type of ballconstruction. It may be used in the core, cover, or one or moreintermediate layers of a golf ball.

Suitable golf ball constructions, including one-piece golf balls,two-piece golf balls, three-piece golf balls and multi-piece golf balls,are described in U.S. patent application Ser. No. 12/261,331, filed onOct. 30, 2008, and in the references cited therein. The compositiondescribed herein may be used in any of the golf balls in which thecomposition described in the '331 application can be used. Of note,however, are golf balls comprising a cover prepared from a polyurethaneor polyurea composition, and a core or intermediate layer prepared fromthe composition as described herein; golf balls comprising a coverprepared from an ionomer composition, and a core or intermediate layerprepared from the composition as described herein; two-piece golf ballscomprising a cover prepared from a polyurethane or polyurea composition,and a core prepared from the composition as described herein; two-piecegolf balls comprising a cover prepared from an ionomer composition, anda core prepared from the composition as described herein; wound golfballs having a cover comprising or prepared from a polyurethane orpolyurea composition, and a core or intermediate layer prepared from thecomposition as described herein; wound golf balls having a covercomprising an ionomer or prepared from an ionomer composition, and acore or intermediate layer prepared from the composition as describedherein.

Also of note are multi-piece golf balls having:

-   -   1. a core comprising the composition as described herein, with        or without filler, with a cover made of any composition known in        the art to be useful as a cover;    -   2. a core comprising the composition as described herein, with        or without filler, used in a multilayer golf ball core with at        least one mantle, with or without filler, and a cover made of        any composition known in the art to be useful as a cover;    -   3. a core made of any composition (including thermoset        compositions such as polybutadiene rubber), with or without        filler with an intermediate layer comprising the composition as        described herein, with or without filler;    -   4. a cover prepared from a polyurethane composition; and a core        prepared from the composition as described herein, further        comprising at least one additional intermediate layer;    -   5. a cover prepared from an ionomer composition, and a core        prepared from the composition as described herein, further        comprising at least one additional intermediate layer;    -   6. a cover prepared from a polyurethane composition, and a core,        further comprising at least one additional intermediate layer        prepared from the composition as described herein; and    -   7. a cover prepared from an ionomer composition, and a core,        further comprising at least one additional intermediate layer        prepared from the composition as described herein.

The golf balls of note may optionally comprise one or more fillers, asdescribed above. The filler may be used in the core and not in themantle, in the mantle and not in the core, or in both the core and themantle.

Furthermore, properties such as hardness, modulus, compression,resilience, core diameter, intermediate layer thickness and coverthickness of golf balls have been found to affect play characteristicssuch as spin, initial velocity and feel of golf balls. Depending on theconstruction and desired characteristics of the golf ball, the core,intermediate layers, and cover may have different resilience,compression or hardness to achieve desired performance characteristics.The compositions described herein may be useful in preparing golf ballswith resilience, compression or hardness gradients within a golf ball.The selection of materials for performance based on these criteria isalso described at length in U.S. patent application Ser. No.12/261,331,filed on Oct. 30, 2008, and in the references cited therein.

In particular, however, the golf balls described herein arecharacterized by a high initial velocity and a high coefficient ofrestitution (COR). More specifically, the compositions described hereinprovide tailored resiliency as indicated by the coefficient ofrestitution (COR). Coefficient of restitution (COR₁₂₅) may be measuredby firing a sphere that is 1.50 to 1.68 inches in diameter at an initialvelocity of 125 feet/second against a steel plate positioned 3 feet fromthe point where initial velocity is determined and dividing the velocityof rebound from the plate by the initial velocity. One may also measureCOR at several initial velocities, develop a correlation and determine aCOR at a specified initial velocity based on the correlation. COR may bedetermined on a sphere prepared from a single composition or a spherehaving two or more layers (for example, a finished golf ball). Oneskilled in the art will recognize that COR cannot be greater than 1.0.

The compositions described herein are highly resilient, that is, theyexhibit high COR values. For spheres prepared from the compositionwithout filler, the compositions provide COR measurements from about0.86 to about 0.90 or higher when measured according to the COR Methoddescribed herein. Any COR value within that range may be considered as“high COR”. As indicated above, the presence of filler reduces the CORroughly proportional to the reduction in volume of the resin fraction ofthe volume of a test sphere. Compositions described herein, whencontaining filler, have COR of greater than about 0.83, for example fromabout 0.83 to about 0.86, or higher.

For a solid test sphere prepared from a single composition, the COR willdepend on a variety of characteristics of the composition, including itshardness. COR will generally increase as hardness is increased. In atwo-piece solid golf ball with a core and a cover, one of the purposesof the cover is to produce a gain in COR over that of the core. When thecontribution of the core to high COR is substantial, a lessercontribution is required from the cover. Similarly, when the covercontributes substantially to high COR of the ball, a lesser contributionis needed from the core.

Moreover, the compositions described herein have a Shore D hardness ofat least about 30, and preferably about 40 to 60, as measured on aformed sphere. The compositions preferably have a Shore D hardness ofabout 50 to 65, as measured on a standard test plaque. In addition, thecompositions described herein preferably have a flexural modulus ofabout 15,000 psi to about 30,000 psi.

The thermoplastic compositions described herein may be useful in a widerange of objects other than, mantles, intermediate layers, cores, andcenters of golf balls. As previously discussed, the compositions, andoptionally foamed compositions, may be used as cores for balls otherthan golf balls. The compositions also may be useful in other sportingequipment applications, particularly in golf shoe cleats, components ofgolf clubs such as golf club face plates or inserts, molded golf clubheads, club head coatings or casings, and fillers for inner cavity of agolf club head, and the like. The compositions may also be used in placeof materials taught in the art for use in club faces, such aspoly-imides reinforced with fillers or fibers, methyl (meth)acrylatecopolymers, carbon-fiber reinforced polycarbonate, materials based onPMMA and crosslinkable monomers, and cross-linked synthetic rubber. Thecomposition may also be substituted for the cured acrylic monomer,oligomer, polymer used to impregnate wood club heads, for rubber-likeelastic cores in club heads, and for molded polyurethane club heads. Assuch, golf club heads may be prepared having a front striking faceadapted to strike a ball and an insert mounted on the striking face,said insert comprising a molded article comprising the compositionabove. In addition, golf club heads comprising a metal body and aninsert plate secured to the forward striking surface of the metal bodyand made of the composition above laminated with an outer metal layerformed with grooves. In addition, this invention also includes a golfclub having a shaft with a club head affixed to the shaft, wherein theclub head is described above, having a component comprising thecomposition above.

The composition may also be useful for preparing molded articles thatare footwear structural components, provide shape support for footwearconstruction, such as heel counters, toe puffs, soles and cleats. “Heelcounter” as used herein refers to a stiff, curved piece that providesshape and structure to the heel area of a shoe. “Toe puff” or “toe box”as used herein refers to a stiff, arched piece that provides shape andstructure to the toe area of a shoe. “Sole” as used herein refers to astiff, generally flat piece that provides shape and structure to thebottom of a shoe. These structural components may be incorporated intothe internal structure of the shoe and covered with additionalcomponents for wear and/or appearance.

The composition described herein may also be useful in non-sporting goodapplications such as caulking materials, sealants, modifiers for cementand asphalt, and coatings. The compositions may also be useful in toys,decorative objects, and containers for inert materials.

The following examples are provided to describe the invention in furtherdetail. These examples, which set forth a preferred mode presentlycontemplated for carrying out the invention, are intended to illustrateand not to limit the invention.

EXAMPLES Testing Criteria for Examples

Coefficient of Restitution (COR) was measured by firing aninjection-molded neat sphere of the resin having the size of a golf ballfrom an air cannon at several velocities over a range of roughly 60 to180 fps. The spheres struck a steel plate positioned three feet awayfrom the point where initial velocity is determined, and reboundedthrough a speed-monitoring device located at the same point as theinitial velocity measurement. The COR of each measurement was determinedas the ratio of rebound velocity to initial velocity. The individuallydetermined COR measurements were plotted as a function of initialvelocity, and COR at 125 fps (i.e. COR₁₂₅) was determined by linearregression.

As used in the Examples below, melt index (MI) refers to melt index asdetermined according to ASTM D1238 at 190° C. using a 2160 g weight,with values of MI reported in g/10 minutes.

As used herein, “Shore D hardness” of a material is measured generallyin accordance with ASTM D-2240 either on a plaque or on the curvedsurface of a molded sphere. Shore D hardness of multilayer spheres ismeasured with all layers present. When a hardness measurement is made ona dimpled sphere, Shore D hardness is measured at a land area of thedimpled sphere.

Flex Modulus was measured according to ASTM D790, Method 1, Procedure A,employing a 3-point test fixture with a 2-inch span length and acrosshead speed of 0.50 inches/minute. The method provides a measurementof the Tangent Modulus of Elasticity (3-Point Flex Modulus).

PGA Compression was measured using an “Atti” testing device according tostandard procedures for that instrument. For accurate comparison ofcompression data, the diameter of the balls was corrected to 1.68 inchdiameter using accepted methods, such as shimming.

Materials Used:

-   EAC-1: An ethylene/acrylic acid (AA)/n-butyl acrylate (nBA)    terpolymer with 12 weight % of AA and 17.6 weight % of nBA, with an    MI of 95.-   EAC-2: A 50/50 blend by weight of an ethylene/AA/nBA terpolymer with    20.5 weight % of AA and 4.0 weight % of nBA, with an MI of about 750    with an ethylene/M copolymer with 21.0 weight % of AA and an MI of    300.-   EAC-3: An ethylene/M/nBA terpolymer with 10.5 weight % of AA and    15.5 weight % of nBA, with an MI of 60.-   EAC-4: An ethylene/M/nBA terpolymer with 6.2 weight % of AA and 28.0    weight % of nBA, with an MI of 60.-   EAC-5: An ethylene/acrylic acid/nBA terpolymer with 6.2 weight % of    AA and 28.0 weight % of nBA, with an MI of 300.-   EAC-6: An ethylene/MAA/nBA terpolymer with 15.7 weight % of MAA and    7.8 weight % of nBA, with an MI of 122.-   EAC-7: An ethylene/MAA/nBA terpolymer with 19.5 weight % of MAA and    4.0 weight % of nBA, with an MI of 265.-   EAC-8: An ethylene/MAA/nBA terpolymer with 17.5 weight % of MAA and    8.0 weight % of nBA, with an MI of 280.-   EAC-9: An ethylene/AA/nBA terpolymer with 17.6 weight % of AA and    4.0 weight % of nBA, with an MI of 285.-   EAC-10: An ethylene/AA/nBA terpolymer with 15.4 weight % of AA and    8.0 weight % of nBA, with an MI of 300.-   EAC-11: An ethylene/AA/nBA terpolymer with 21.3 weight % of AA and    2.0 weight % of nBA, with an MI of 275.-   EAC-12: An ethylene/AA/nBA terpolymer with 21.4 weight % of AA and    4.0 weight % of nBA, with an MI of 275.-   EAC-13: An ethylene/MAA/nBA terpolymer with 9.0 weight % of MAA and    15.5 weight % of nBA, with an MI of 60.-   MB-1: A Mg(OH)₂ concentrate with 49 weight % Mg(OH)₂ in EAC-5.-   Oleic acid was a commercial grade material obtained from Chemtura    Industries of Middlebury, Conn., under the tradename INDUSTRENE 106.-   Erucic acid was obtained as JARIC 22:1 from Jarchem Industries Inc.    of Newark, N.J. or as Prifrac 2990 from Uniqema of Wilton, England.-   Filler: crystalline tungsten powder available from Alldyne Powder    Technologies, Kulite Tungsten Corporation, with a specific gravity    of 19.3 g/cc.

Blends were prepared according to the following general procedure.Employing a Werner & Pfleiderer twin screw extruder, organic acid, anethylene acid copolymer, and neutralizing agent (MB-1 and/or Mg(OH)₂were melt blended. The amounts of the acid and copolymer were added sothat the resulting blend contained 25 to 45 weight % of the organicacid. The blend was treated with sufficient MB-1 and/or Mg(OH)₂ so thatthe acid moieties of the organic acid and the acid copolymer werenominally neutralized to the level indicated.

General extrusion conditions for making the blends identified in Table 2are shown in Table 1.

TABLE 1 Zone 1 Zone 2-4 Zone 5 Die Melt Temperature ° C. 140-180 265-275255-265 200-220 255-275 Vacuum inches 28 Screw Speed rpm 175-250 Totalrate (lb/h) 15-25

The components of the blends are summarized in Table 2. In the columnlabeled “Organic Acid Type,” “100 O ” indicates that the organic acidwas 100% of an as-obtained commercial grade of oleic acid, and “50 O/50E” indicates that the organic acids were as-obtained commercial gradesof oleic acid and erucic acid in a 50/50 ratio by weight. The columnlabeled “Mg(OH)₂” shows the amount of Mg(OH)₂ calculated to be presentin the composition based on the amount of MB-1 masterbatch included inthe composition.

Comparative Examples C1 and C2 are blends comprising ethylene terpolymerwith lower amounts of acrylic acid and higher amounts of n-butylacrylates with a lower MI, neutralized with MB-1, prepared usingprocedures similar to those used for the Examples. Comparative ExampleC3 is a blend prepared from EAC-5, a terpolymer comprising low amountsof acrylic acid and high amounts of n-butyl acrylate with a high MI,nominally neutralized to about 115% with Mg(OH)₂.

TABLE 2 Weight % Example Terpolymer used Organic Acid Type TerpolymerAcid MB-1 Mg(OH)₂ C1 EAC-3 100 O 52.55% 35.00% 12.45% 6.10% C2 EAC-4 100O 50.10% 35.00% 14.90% 7.30% C3* EAC-5 100 O   45%   35% 0 n/a  1 EAC-2100 O  44.0% 36.70%  19.3% 9.5%  2 EAC-11  50 O/50 E 43.37% 40.48%16.15% 7.92%  3 EAC-11  50 O/50 E 37.21% 43.99% 18.80% 9.21%  4 EAC-11100 O 52.58% 30.67% 16.75% 8.21%  5 EAC-11 100 O 42.60% 40.30% 17.10%8.38%  6 EAC-7 100 O 50.43% 29.47% 20.10% 9.85%  7 EAC-7 100 O 48.42%32.18% 19.40% 9.51%  8 EAC-7 100 O 41.17% 38.65% 20.18% 9.89%  9 EAC-7100 O 35.76% 38.08% 26.16% 12.82%  10 EAC-12 100 O 52.38% 31.63% 15.99%7.84% 11 EAC-12 100 O 40.85% 41.92% 17.23% 8.44% 12 EAC-12 100 O 45.46%34.29% 20.25% 9.92% 13 EAC-12  50 O/50 E 44.70% 39.31% 15.99% 7.83% 14EAC-9 100 O 52.02% 30.53% 17.45% 8.55% 15 EAC-9 100 O 52.61% 32.10%15.29% 7.49% 16 EAC-9 100 O 44.14% 40.09% 15.76% 7.72% 17 EAC-9 100 O47.75% 30.96% 21.29% 10.43%  18 EAC-9 100 O 40.65% 39.56% 19.78% 9.69%19 EAC-8 100 O 51.18% 30.82% 18.00% 8.82% 20 EAC-8 100 O 51.13% 29.41%19.47% 9.54% 21 EAC-8 100 O 41.86% 36.84% 21.30% 10.44%  22 EAC-8 100 O34.24% 38.19% 27.56% 13.51%  23 EAC-10 100 O 54.66% 29.94% 15.41% 7.55%24 EAC-10 100 O 40.86% 39.77% 19.36% 9.49% 25 EAC-10 100 O 44.12% 36.48%19.39% 9.50% 26 EAC-1 100 O 54.81% 36.54%  0.00%  8.7% 27 EAC-6 100 O39.80% 40.00% 20.20% 9.90% 28 EAC-6 100 O 45.42% 37.50% 17.08% 8.37% C29EAC-3 100 O 50.96% 34.92% 14.11% 6.59% C30 EAC-3 100 E 47.90% 39.27%12.82% 6.24% C31 EAC-4 100 O 51.70% 34.95% 13.35% 6.54% C32 EAC-4 100 E47.69% 39.76% 12.55% 5.96% C33 EAC-13 100 O 50.97% 35.13% 13.90% 6.43%C34 EAC-13 100 E 48.89% 38.68% 12.43% 6.09% *Amounts in C3 are targetedamounts; “n/a” means “not available”.

In Table 3, the column labeled “Adjusted Base Resin MI” indicates the MIcalculated from a weighted logarithmic average of the non-neutralizedmixture of terpolymers present in the composition according to thefollowing formula:

MI _(polymer1) ^(fraction1) ×MI _(polymer2) ^(fraction2) × . . . ×MI_(polymerN) ^(fractionN) wherein fraction1+fraction2+ . . .+fractionN+100%

“% Nominal Neutralization” is calculated by stoichiometric principlesbased on the total amount of acid groups present in the terpolymer(s)and the organic acid(s), and on the amount of Mg(OH)₂ added to thethermoplastic composition. The total amount of acid groups includes theacid groups in the polymer carrier in the masterbatch, if a masterbatchwas used.

“Measured MI” is the melt index of the composition after blending.

TABLE 3 Adjusted % Nominal Measured Example Base Resin MI NeutralizationMI C1 71 102% 1.00 C2 74 145% 1.00 C3 300  115%* n/a**  1 437 124% 0.06 2 279 103% 0.29  3 280 123% 0.34  4 278 105% 0.01  5 279 105% 0.37  6270 150% 0.31  7 270 142% 0.89  8 271 143% 2.58  9 274 195% 0.93 10 27899% 0.17 11 279 105% 0.48 12 279 134% 0.06 13 279 102% 0.25 14 287 122%0.16 15 287 104% 0.46 16 287 104% 1.12 17 288 154% 0.01 18 288 135% 0.3519 283 138% 2.21 20 283 152% 0.01 21 284 160% 6.85 22 286 215% 4.55 23300 114% 0.29 24 300 138% 0.75 25 300 142% 0.21 26 95 135% 0.35 27 146153% 0.95 28 140 129% 1.05 C29 73 124% 0.91 C30 72 127% 1.43 C31 72 124%2.63 C32 72 121% 5.94 C33 73 120% 3.68 C34 72 125% 7.74 *Amounts in C3are targeted amounts. *“n/a” means “not available”.

Thermoplastic Spheres

The compositions were molded into spheres 1.53 to 1.55 inches indiameter using the molding conditions for making spheres that are shownin Table 4. General molding conditions are reported as ranges, withspecific conditions for selected examples indicated. The resultsobtained by measuring the example spheres are summarized in Table 5.

TABLE 4 Molding Conditions for Spheres Melt Zone Mold Inject Fill PackPack Cool Example (° C.) (° C.) (s) (s) (s) (mPa) (s) General 190-23020-50 80-90 10-30 55-75 50-160 75-80

TABLE 5 Example Weight (g) Diameter (in) Sp.Gr. (g/cc) Shrink (%) C130.669 1.5393 0.980 3.11% C2 30.443 1.5355 0.980 3.35% C3 — — — —  131.430 1.5431 0.997 2.87%  2 29.838 1.530 0.963 3.70%  3 30.142 1.5370.970 3.28%  4 31.285 1.543 0.986 2.86%  5 31.320 1.545 0.988 2.76%  631.579 1.549 0.991 2.51%  7 31.377 1.549 0.983 2.50%  8 30.950 1.5410.983 2.98%  9 31.464 1.539 1.001 3.11% 10 31.296 1.540 0.998 3.07% 1131.030 1.539 0.992 3.15% 12 30.674 1.542 0.976 2.91% 13 29.964 1.5310.972 3.60% 14 31.289 1.551 0.993 2.37% 15 31.142 1.546 0.978 2.67% 1630.947 1.545 0.974 2.77% 17 31.042 1.543 0.982 2.88% 18 30.923 1.5380.988 3.17% 19 30.766 1.536 0.985 3.30% 20 31.396 1.549 0.989 2.53% 2131.050 1.536 0.999 3.30% 22 31.386 1.535 1.010 3.36% 23 30.957 1.5430.981 2.87% 24 31.182 1.543 0.991 2.88% 25 30.050 1.535 0.967 3.36% 2630.700 1.5382 0.988 3.18% 27 30.638 1.5480 0.962 2.56% 28 30.487 1.54730.958 2.60% C29 30.550 1.561 0.936 1.75% C30 30.425 1.563 0.929 1.63 C3130.743 1.565 0.935 1.50% C32 30.478 1.564 0.928 1.54% C33 30.718 1.5640.936 1.55% C34 30.583 1.565 0.931 1.51%

Examples C1, 27 and 28 were also filled with tungsten filler and moldedinto spheres as summarized in Table 6. The amount of tungsten wasbetween 15 and 20 weight %, based on the total weight of thethermoplastic composition, or about 0.75 to 1.25 volume % of tungstenbased on the total volume of the thermoplastic composition. “PBR” is aconventional filled thermoset polybutadiene rubber core for comparison.

TABLE 6 Resin Weight Diameter Specific Gravity Example Used (g) (in)(g/cc) Shrink (%) C4 C1 36.803 1.550 1.151 2.47% 29 27 36.832 1.55131.151 2.35% 30 28 37.115 1.5540 1.152 2.18% PBR — 37.158 1.5516 1.1582.34%

The spheres were tested for Coefficient of Restitution, PGA Compressionand Shore D Hardness. The results are reported in Table 7.

TABLE 7 Example COR₁₂₅ PGA Compression Shore D C1 0.859 101.0 45.8 C20.826 74.6 41.8 C3 na na na  1 0.880 126.7 59.6  2 0.886 123.5 55.3  30.889 117.7 51.5  4 0.884 141.2 58.1  5 0.889 131.4 54.5  6 0.835 121.753.6  7 0.835 115.2 52.6  8 0.853 110.8 49.7  9 0.853 112.2 48.2 100.866 139.5 59.1 11 0.888 126.6 53.3 12 0.872 130.6 57.0 13 0.884 123.355.1 14 0.865 123.3 54.2 15 0.866 125.0 52.7 16 0.882 115.9 49.5 170.862 120.8 58.1 18 0.880 119.8 50.7 19 0.828 106.9 47.3 20 0.842 111.651.1 21 0.844 101.7 46.8 22 0.847 103.9 47.0 23 0.870 116.9 53.6 240.875 110.6 48.3 25 0.875 101.2 49.6 26 0.868 117.8 47.7 27 0.868 96.647.8 28 0.866 97.2 48.6 C29 0.850 82.4 45.2 C30 0.850 74.6 42.4 C310.807 51.1 35.8 C32 0.805 41.2 33.6 C33 0.817 61.8 39.2 C34 0.817 56.836.4 Filled Compositions C4 0.839 87.5 44.8 29 0.853 99.6 47.8 30 0.85097.8 47.7 PBR 0.692 65.0 40.2

While certain preferred embodiments of the invention have been describedand specifically exemplified above, it is not intended that theinvention be limited to such embodiments. Various modifications may bemade without departing from the scope and spirit of this invention, asset forth in the following claims.

1. A golf ball comprising a core and a cover and optionally at least oneintermediate layer positioned between the core and the cover, whereinthe core or an intermediate layer when present comprises a thermoplasticcomposition and the thermoplastic composition comprises or is preparedfrom: (a) at least one aliphatic, monofunctional organic acid having 4to 36 carbon atoms, wherein the longest carbon chain of the acid isoptionally substituted with from one to three substituents independentlyselected from the group consisting of C₁ to C₈ alkyl groups; (b) atleast one ethylene acid copolymer consisting essentially ofcopolymerized comonomers of ethylene, from about 12 to about 25 weight %of copolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid, and from about 0.5 to about 10 weight % ofcopolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid ester, based on the total weight of theethylene acid copolymer, said at least one ethylene acid copolymerhaving a melt index from about 200 to about 600 g/10 minutes measuredaccording to ASTM D1238 at 190° C. using a 2160 g weight; wherein thecombined acid moieties of (a) and (b) are nominally neutralized to alevel from about 90% to about 220%; and wherein the thermoplasticcomposition when formed into a sphere of 1.50 to 1.68 inches in diameterhas a coefficient of restitution equal to or greater than 0.860, saidcoefficient of resilience being measured by firing the sphere at aninitial velocity of 125 feet/second against a steel plate positioned 3feet from the point where initial velocity is determined and dividingthe velocity of rebound from the plate by the initial velocity and has aPGA compression greater than
 110. 2. The golf ball of claim 1 whereinthe core comprises the thermoplastic composition.
 3. The golf ball ofclaim 1 wherein the amount of the at least one organic acid is fromabout 35 to about 45 weight %, based on the total weight of thethermoplastic composition.
 4. The golf ball of claim 1 wherein the atleast one organic acid comprises a linear, unsaturated organic acidhaving from 16 to 24 carbon atoms.
 5. The golf ball of claim 4 whereinthe at least one organic acid comprises oleic acid.
 6. The golf ball ofclaim 1 wherein the C₃ to C₈ α,β ethylenically unsaturated carboxylicacid is acrylic acid or methacrylic acid or a combination of acrylicacid and methacrylic acid.
 7. The golf ball of claim 1 wherein thethermoplastic composition further comprises one or more fillers.
 8. Thegolf ball of claim 7 wherein the filler comprises barium sulfate,titanium powder or zinc oxide.
 9. The golf ball of claim 7 wherein thecore comprises the thermoplastic composition.
 10. The golf ball of claim1 wherein an intermediate layer comprising the thermoplastic compositionis present.
 11. The golf ball of claim 1 comprising a cover preparedfrom a polyurethane composition.
 12. The golf ball of claim 1 comprisinga cover prepared from an ionomer composition.
 13. A thermoplasticcomposition comprising or prepared from: (a) at least one aliphatic,monofunctional organic acid having 4 to 36 carbon atoms, wherein thelongest carbon chain of the acid is optionally substituted with from oneto three substituents independently selected from C₁ to C₈ alkyl groups;(b) at least one ethylene acid copolymer consisting essentially of 3 0copolymerized comonomers of ethylene, from about 12 to about 25 weight %of copolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid, and from about 0.5 to about 10 weight % ofcopolymerized comonomers of at least one C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid ester, based on the total weight of theethylene acid copolymer, said at least one ethylene acid copolymerhaving a melt index from about 200 to about 600 g/10 minutes measuredaccording to ASTM D1238 at 190° C. using a 2160 g weight; wherein thecombined acid moieties of (a) and (b) are nominally neutralized to alevel from about 90% to about 220%; and wherein the thermoplasticcomposition when formed into a sphere of 1.50 to 1.68 inches in diameterhas a coefficient of restitution equal to or greater than 0.86, measuredby firing the sphere at an initial velocity of 125 feet/second against asteel plate positioned 3 feet from the point where initial velocity isdetermined and dividing the velocity of rebound from the plate by theinitial velocity and has a PGA compression greater than
 110. 14. Thecomposition of claim 13 wherein the amount of the at least one organicacid is from about 35 to about 45 weight %, based on the total weight ofthe thermoplastic composition.
 15. The composition of claim 13 whereinthe at least one organic acid comprises a linear, unsaturated organicacid having from 16 to 24 carbon atoms.
 16. The composition of claim 13wherein the at least one organic acid comprises oleic acid.
 17. Thecomposition of claim 13 wherein the C₃ to C₈ α,β ethylenicallyunsaturated carboxylic acid is acrylic acid or methacrylic acid or acombination of acrylic acid and methacrylic acid.
 18. The composition ofclaim 13 further comprising one or more fillers.
 19. The composition ofclaim 13 that is foamed by the addition of at least one physical orchemical blowing or foaming agent or by blending with polymeric,ceramic, metal, and glass microspheres.
 20. An article comprising thecomposition of claim 19.